The objective of the Metabolism core is to provide the to PPG investigators the scientific and technical support for the execution of biochemical analyses of blood and myocardial tissue samples from all four Projects in the PPG. The Core will perform metabolic and isotopic tracer analysis of blood and tissue from the dogs studied in Projects 1, 2 and 3, and will oversee the experiments with doubly labeled water in mice and dogs in Project 1. The Core will also assess the expression and activity of selected proteins, measure the content of key regulatory metabolites (e.g ATP, lactate, etc), measure mRNA expression for selected genes, and plasma hormone levels. The measurement of Inflamatory cytokines for Project 1 will be performed by the Core. All of the expertise and equipment necessary for these measurements is in place.